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A Guide to Furnace Troubleshooting for Homeowners


You may wake up in the middle of the night feeling colder than usual because your furnace may have stopped working.

Most of the time, furnace problems turn out to be simple issues and easy to be fixed. With proper furnace maintenance, you can expect your furnace system to last a long time.

Read this blog and learn the common furnace problems and how to fix them.


Examine Your Thermostat


It might surprise you to know how often people make service calls without first checking their thermostats. Before assuming the worst, make sure yours is set to “heat” and it's set at least five degrees above the temperature of the house.

If your thermostat is battery-powered, take a moment to make sure the batteries aren't dead. If your thermostat is wired, check the breaker that connects to it and make sure it's on.

On automatic thermostats, you should also make sure the date and time are displayed correctly and that it isn't currently set to “off” with a timer.


Check the Filter


After inspecting your thermostat, the next-easiest troubleshooting method is to look at the air filter. If the furnace is running but not producing enough heat, you may have a clogged or dirty filter.

To determine whether the filter needs to be changed, remove it from the system and hold it up to shine a light through it. If no light goes through, that means the filter is dirty.

You can also tell that the filter needs to be replaced if the air blowing through your home's ventilation is dusty.

Replacing your air filter at least twice per year will prevent problems and help your HVAC system last longer.


Inspect the Furnace Door Safety Switch


On gas-powered furnaces, there should be a safety switch on the access panel that prevents the system from turning on while the door is open.

Make sure the access panel door is closed.


Test the Home Circuit Breaker


If your furnace isn't functioning at all and none of the prior methods worked, find your home's breaker panel and identify the circuit that controls the furnace.

Manually test the breaker by flipping it back and forth, and see if it will stay in the “on” position. Then test your furnace again to see if it works.


The Fan Test


Go to the thermostat and place the fan switch on. The fan should start to blow air, and that way you can ensure you have power to the furnace. If the fan doesn’t run, then the motor has failed or there may be other issues.


Contact Nexstar Mechanical Service for Advanced Furnace Troubleshooting


If furnace troubleshooting doesn't seem to solve the problem, it may be time to call a professional.

Nexstar Mechanical Services in Winnipeg has you covered with full-service furnace solutions.

Whether you're preparing for winter or waking up in the middle of the night, contact Nexstar today to get your HVAC system up and running again.

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